Core A-GI Tissue Resource will coordinate histopathological assessment of all GI tissues collected from three local Tucson-area hospitals and existing banks of normal and neoplastic GI tissues. Approximately 700 colorectal, esophageal and pancreatic cancer patients are seen annually at the Arizona Cancer Center (ACC), the Southern Arizona Veterans Administration Medical Center (SAVAMC) and Tucson Medical Center (TMC). Existing tissue banks contain over 5000 frozen and fixed samples of normal intestinal tissues, more than 1500 colon adenomas and over 800 specimens from patients with Barrett?s esophagus have been collected and stored during the course of cancer prevention studies conducted at the ACC and SAVAMC. Standard methods of preservation and storing tissues will be employed to facilitate measurement of desired endpoints. Special services, such as laser capture microdissection, will be available. The activities of Core A-GI Tissue Resource will be coordinated with other proposed resources, to ensure collection of tissues from patients participating in the proposed clinical trials, standards of marker measurement in tissues, adequacy of statistical input into design of trials and evaluation of results from patient studies. With the assistance of Core E-Informatics, a comprehensive database for all samples within the GI Tissue Resource will be developed. This database will be designed so that it can be interrogated for patient related information, including outcome data, and specific prognostic and/or predictive factors obtained during the course of this research effort. Frozen and paraffin embedded tissue will be saved permanently. Prior to collection of tissue an informed consent will be procured. The consent will follow the guidelines established by National Action Plan on Breast Cancer (NAPBC) with approval and input from the Institutional Review Boards of the University Medical Center and the local participating hospitals. A Human Tissue Acquisition and Pathology Resource Committee, under the umbrella of the ACC, will be established to monitor this essential activity.